11:1 too high for pump gas?

IMM Engines insisted I not go over 9.4 on the 408 stroker engine he is building for me using pump gas in my daily driver dodge ram. Pump gas is crap and it isn't getting any better. I'm running a 5.9 engine in it now ...completely stock engine with add ons with a SCT tune on it using 93 octane gas and hear detonation ever so often! Stock compression!
From what I've read on line doing research on how far I can go with static compression on pump gas it all comes down to dynamic compression ratio. Using DCR if factors in elevation, cam intake valve closing(bleed off), and other factors. The DCR should fall between 8.00-8.20 DCR on pump gas using iron heads ... you will be OK. I can't remember what is allowable in DCR using aluminum heads but don't remember seeing 10.00 in DCR. Another words you can go over 8.20 with aluminum.

Here is the calculator: Wallace Racing: Dynamic Compression Ratio Calculator

I went thorough the "I can change out the head gaskets and get 9.8 static compression and fall in the safe DCR range" but was told "is that little extra compression really worth it on the street when you can be facing detonation issues?"

Heads iron or aluminum, cam(bleed off), timing, altitude, engine cooling efficiency, outside temperature, all play a huge roll in what you can get away with on pump gas.